(1) Field of the Invention
The present invention relates to a portable dialogue supporting apparatus which converts a speech-inputted source language sentence into a target language and outputs the converted sentence in speech or text form.
(2) Description of the Related Art
Dialogue supporting systems which translate speech input have been developed as software for workstations and personal computers. In a laboratory environment, performance has reached a practical level for users familiar with their usage, in the case where the scope of conversation is limited to applications for travel conversation, and the like. However, in terms of usability, performance has not yet reached a level that allows usage by the average overseas tourist on an actual trip. In order to improve usability, packaging in readily-portable size hardware and implementation in a user interface that is easy to master and operate, is necessary.
Conventionally, usability is improved by limiting the functions and performance of speech translation software developed for workstations and personal computers, and transplanting these into a Personal Digital Assistant (PDA) (see “AN EXPERIMENTAL MULTILINGUAL SPEECH TRANSLATION SYSTEM”, Kenji Matsui et al., Workshops on Perceptual/Perceptive User Interfaces 2001, ACM Digital Library, ISBN 1-58113-448-7, for example).
In the sample sentence-based translation method using speech input, many thousands of sample sentences need to be prepared in order to cover the average travel conversation, and depending on the result of speech recognition, there are cases where many sample sentences appear as candidates. For example, in the case where words having a high frequency of appearance, in terms of the sample sentences as a whole (for example, ┌ (aru)┘ (be, have), ┌ (en)┘ (Yen), and so on), are accurately recognized in the speech recognition but the rest of the sample sentences cannot be recognized satisfactorily, the number of sample sentences selected as candidates and presented to the user consequently increases. In such cases, it is not easy for the user to select a desired sample sentence from among the candidate-sample sentences. In particular, when the display device for viewing the list of candidate-sample sentences is small and the number of sample sentences that can be viewed simultaneously is considerably small, selecting a desired sample sentence from among the candidates presented becomes even more difficult. Furthermore, when a sample sentence that is similar to the desired sample sentence is found while looking through the candidate-sample sentences, there are many instances where there is hesitation in deciding as to whether to select such sample sentence or to search for a closer matching sample sentence. As such, a function for aiding selection for large amounts of candidate-sample sentences is necessary.
For this reason, the applicant of the present application proposes a speech conversion apparatus that enables a flexible search by searching out a sample sentence based on the dependence relationship of words within the sample sentence, and can improve the usability of displayed details (see Japanese Laid-Open Patent Application No. 2003-288339 Publication, for example).
However, the improvement of sample sentence search accuracy has limitations. In particular, in the case where the display device for viewing the list of candidate-sample sentences is small and the number of sample sentences that can be viewed simultaneously is considerably small, selecting a desired sample sentence from among the insufficiently presented candidates is difficult.
Thus, the present invention is conceived in view of the above-mentioned circumstances, and has as an objective to provide a dialogue supporting apparatus that can easily select a desired sample sentence from among candidate-sample sentences corresponding to inputted speech.